I bought a 98 vic that had a motor out of a 98 Cobra. When I bought the car that motor was bad so I got one with low miles out of a wrecked thunderbird(98) and transplanted it in this car. It runs great and gets 23mpg but the issue I am having is the fan doesn't always come on when I think it should. The high and low does work when it does come on. On the bad motor I pulled out, it had a sensor that looks like a temp sensor screwed into the block,under the intake,drivers side, right below where the head bolts to the block. I unscrewed it and just layed it somwhere to where the block can heat up the plug till I figure out what it is what I should do. Soooo heres my question, On these two motors. Where is the sensor that runs the cooling fan and wheres the sensor that runs the temp gage? Or does one sensor run the gage and fan? And does any one have pictures so I know exactly what I am looking at? Sorry for the long post and thanks for any and all help!

The ECT (engine coolant sensor) is mounted on the passengers side of the intake near the alternator. The CHT cylinder head temperature) sensor mounts under the manifold on the drivers side, in the cylinder head. The CHT controls the fan, the ECT runs the gauge. The temp gauge usually gets to a little over half way up the scale when the fan comes on.

The motor in the car now doesn't have a place for the CHT or something is blocking it and I have totally looked over it.Is it possable this motor doesn't have one or do ALL 4.6 motors have one and I have just missed it?

Correct me if I am wrong(which I usually am) but as long as that sensor is in the passage where the antifreeze travels it should work just like the regular temperature gage? Worse case make the fan come on a little earlier than normal? Sorry for all the questions but other than that plug right next to thermostat neck in the intake, I don't know where else I could put it at. Thanks again for your help!

That should work. The reason they put it in the cylinder head is that a total loss of coolant will have no hot coolant in the upper area to sense the heat. As long as it doesn't lose the coolant like a blown hose, you should be alright.

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